ECCouncil 312-50v13 (Certified Ethical Hacker v13) Practice Test 16

Question 150

A follow-up review must reduce the risk revealed here: An API gateway keeps accepting obsolete handshake versions for old partners, and the security team must remove downgrade paths rather than merely advertising a modern preferred version. Which defensive measure fits the specific failure mode?

  1. Enforce full-disk encryption with secure boot and recovery-key controls
  2. Enforce modern minimum TLS versions and remove unsafe fallback
  3. Guarantee unique nonces per encryption key and rotate affected keys
  4. Authenticate ephemeral key exchange with validated peer certificates

Explanation

Correct Answer

B:

Strong negotiation policy keeps a transient handshake failure from authorizing obsolete protocol use. The specific weakness being corrected is that protocol downgrade attacks exploit permissive fallback and weak minimum-version policy to force connections onto weaker negotiated security.

Incorrect Answers

A:

At-rest encryption reduces exposure after physical theft, while platform integrity and key escrow govern startup trust and legitimate recovery; the specific root cause belongs to TLS downgrade weakness, beyond this control's intended scope.

C:

Nonce-generation discipline protects the authentication construction, while key rotation limits exposure after uniqueness guarantees have failed; it would improve AES-GCM nonce reuse, not directly correct the reported TLS downgrade weakness issue.

D:

Certificate verification prevents man-in-the-middle key substitution while ephemeral elliptic-curve exchange supports fresh traffic keys; the measure addresses a different trust boundary from the TLS downgrade weakness finding.

Question 151

The post-assessment action plan cites this evidence: A search-result snippet contains a fake instruction to the internal security assistant to send credentials to a third-party endpoint before answering the analyst's legitimate question. Which corrective measure should be prioritized?

  1. Update the threat model when data flows or trust boundaries change
  2. Record black-box coverage limitations in the final report
  3. Treat retrieved content as untrusted data and constrain tool privileges
  4. Limit backup read permissions and enforce authenticated access

Explanation

Correct Answer

C:

Instruction separation, restricted tool permissions, and output validation reduce the chance that untrusted document text can redirect an automated assessment workflow. That correction is linked to the fact that prompt injection places adversarial instructions inside lower-trust material that a language model reads as data; the trust boundary fails if that text gains control authority.

Incorrect Answers

A:

A design-level review must track new integrations and privileges; otherwise earlier assumptions stop representing the system being protected; its security benefit applies principally to threat modeling, not the defect described; the tested fault instead involves prompt injection of an assessment assistant.

B:

The conclusion should describe the outside-in vantage point; inaccessible authenticated functions cannot be declared secure merely because this test did not reach them; the exposure here is prompt injection of an assessment assistant, which calls for another protective mechanism.

D:

Access control and private storage prevent unauthorized retrieval; encryption is beneficial but cannot replace correct authorization for disclosed keys or URLs; this is relevant to a separate confidentiality scenario, rather than the identified exposure; the tested fault instead involves prompt injection of an assessment assistant.

Question 152

A controlled investigation yields this observation: A remote security review must evaluate only what an internet client can reach without any internal login. How should the team identify the underlying behavior?

  1. CVSS base score
  2. Authenticated vulnerability scan
  3. Unauthenticated assessment
  4. Scanner credential exposure

Explanation

Correct Answer

C:

Unauthenticated scanning assesses exposed services and observable configuration from a chosen network vantage point, not hidden local state. For a production safeguard, operators can report unauthenticated blind spots and pair them with approved internal checks; a remote-only result cannot establish that installed packages, local permissions, or dormant services are patched without additional evidence.

Incorrect Answers

A:

CVSS base metrics characterize intrinsic exploitability and impact; local exposure and business consequences are captured separately through context or environmental assessment; the test record points specifically to unauthenticated assessment, not this separate mechanism.

B:

Credentialed scanning examines installed versions, configurations, and local patch state; network-only checks may miss software with no exposed banner; that behavior is distinct from the unauthenticated assessment finding being classified.

D:

Scanning credentials are high-value secrets; tool compromise can turn routine assessment infrastructure into a privileged access path; the defining symptom in the prompt is associated with unauthenticated assessment instead.

Question 153

A security change request summarizes the problem as follows: A Unix file server offers exports to a broad subnet and trusts client-supplied ownership data, allowing nonadministrative machines to view unintended directories. Which remediation is best suited to it?

  1. Restrict RPC exposure to trusted administrative network segments
  2. Disable anonymous enumeration and review guest or null-session policies
  3. Restrict share listing and access through SMB permissions and segmentation
  4. Disable external VRFY responses or normalize recipient disclosure
  5. Constrain NFS exports to intended clients with least-privilege mappings

Explanation

Correct Answer

E:

Host restrictions, secure versions, and root squashing where appropriate reduce remote mounting and privilege-mapping abuse. The underlying condition is that NFS exports describe filesystems available to network clients; export policies can expose directories even when the server's local permissions appear sound.

Incorrect Answers

A:

Filtering management reachability limits endpoint metadata leakage and reduces the chance that remote RPC interfaces are reachable by untrusted clients; the measure addresses a different trust boundary from the NFS export disclosure finding.

B:

Explicitly limiting unauthenticated SMB and RPC access prevents account and share disclosure while preserving required authenticated service use; the required correction concerns NFS export disclosure, so this is not the targeted control.

C:

Share and NTFS permissions plus network isolation reduce unauthorized resource browsing even when SMB must remain available to staff; its security benefit applies principally to SMB share enumeration, not the defect described; the tested fault instead involves NFS export disclosure.

D:

Reducing account-validity feedback limits mailbox harvesting without blocking ordinary SMTP acceptance and queued delivery; the exposure here is NFS export disclosure, which calls for another protective mechanism.

Question 154

The owner asks for a durable safeguard against the issue demonstrated here: A directory account can enumerate service principal names freely while several privileged services use human-chosen passwords that are not rotated. What is the best response?

  1. Review reverse zone permissions and publicly visible PTR values
  2. Limit unintended public exposure of internal service records
  3. Disable external VRFY responses or normalize recipient disclosure
  4. Manage service-account permissions and use strong managed secrets

Explanation

Correct Answer

D:

Tight account privileges and long, rotated secrets limit subsequent ticket-based password attacks after SPN exposure. The technical basis for the recommendation is that SPNs bind service identities to Kerberos names; directory enumeration can identify service accounts but does not by itself reveal their passwords.

Incorrect Answers

A:

Administrative naming policies limit unintended disclosure, though reverse DNS changes do not remove reachable hosts or vulnerable applications; this is relevant to a separate PTR record enumeration scenario, rather than the identified exposure; the tested fault instead involves Kerberos SPN listing.

B:

Split DNS and zone design keep internal discovery available to clients without unnecessarily exposing internal service topology to the internet; the tested weakness is Kerberos SPN listing, not the DNS SRV discovery configuration addressed here.

C:

Reducing account-validity feedback limits mailbox harvesting without blocking ordinary SMTP acceptance and queued delivery; that safeguard does not directly close the Kerberos SPN listing route highlighted by the test.

Question 155

The post-assessment action plan cites this evidence: The chief executive supposedly requests that the finance director bypass normal approval to release a confidential payment during a board meeting. Which corrective measure should be prioritized?

  1. Use mobile-safe link inspection and out-of-band sign-in verification
  2. Require dual approval for exceptional executive payment requests
  3. Disable unapproved removable media and offer safe found-device reporting
  4. Restrict risky application consent and review delegated grants

Explanation

Correct Answer

B:

A second verifier and trusted callback process resist authority-based fraud even when the message convincingly imitates leadership. The technical basis for the recommendation is that whaling focuses social engineering on senior or high-value leaders whose authority and access make a successful deception especially consequential.

Incorrect Answers

A:

Encouraging navigation through known applications reduces dependence on untrusted SMS links and counterfeit login pages; that change targets smishing, while the confirmed weakness involves whaling.

C:

Device controls block execution or access from unknown media while a reporting route avoids relying only on curiosity-resistant behavior; the measure addresses a different trust boundary from the whaling finding.

D:

Admin review and least-privilege OAuth permissions prevent a deceptive app from acquiring long-lived API access through user approval; the required correction concerns whaling, so this is not the targeted control.

Question 156

Operations asks for a practical correction after the test found: Container builds inherit a permanent cloud access key through an environment template, making the credential reusable by anyone who extracts the image layers. What should the security team recommend?

  1. Grant a task-specific least-privilege service role
  2. Restrict service-account verbs and binding rights at namespace scope
  3. Use short-lived workload identities and centralized secret management
  4. Restrict metadata access and harden metadata token requirements

Explanation

Correct Answer

C:

Federated or role-based temporary credentials remove embedded durable keys and simplify expiration after a build job finishes. It directly addresses this mechanism: long-lived static credentials remain useful after an instance is discarded unless revoked, creating persistent exposure across build artifacts and logs.

Incorrect Answers

A:

Limiting API actions and target resources preserves log writing without granting unrelated account configuration or data deletion authority; the exposure here is static cloud access keys, which calls for another protective mechanism.

B:

Precise API permissions prevent application identities from creating or attaching privileges beyond their workload needs; the action is aimed at Kubernetes RBAC escalation; it leaves the central static cloud access keys condition unresolved.

D:

Workload network controls and hardened metadata APIs reduce credential retrieval from unintended server-side request paths; the tested weakness is static cloud access keys, not the cloud metadata SSRF configuration addressed here.

Question 157

The asset owner wants to stop the verified condition recurring: A developer adds an administrative route to a disallow list but leaves the handler available to unauthenticated clients who know the URL directly. What is the most targeted improvement?

  1. Maintain a complete DNS asset inventory and remove orphaned records
  2. Review certificate issuance and audit publicly exposed hostnames
  3. Protect listed routes with server-side authentication and authorization
  4. Enforce SPF, DKIM, and DMARC with aligned identities
  5. Strip sensitive metadata during document publishing

Explanation

Correct Answer

C:

Routing secrecy and robots exclusions cannot substitute for a check that the requesting identity is allowed to reach the resource. The specific weakness being corrected is that crawler directives tell cooperative bots what not to crawl but remain publicly readable and cannot restrict a human client's direct HTTP request.

Incorrect Answers

A:

Discovered names require ownership and scope checks; an inventory process catches unintended public names before they are forgotten; the proposed improvement would make sense for subdomain wordlist discovery but not as the main fix here; the tested fault instead involves exposed robots instructions.

B:

Monitoring issuance records and inventorying discovered names helps detect unexpected certificates and reduce disclosure through overly broad certificate naming; the specific root cause belongs to exposed robots instructions, beyond this control's intended scope.

D:

These domain-authentication mechanisms help receivers assess spoofed mail and policy handling, though they do not eliminate all social-engineering risk; it would improve email header analysis, not directly correct the reported exposed robots instructions issue.

E:

A publication workflow that sanitizes document properties reduces identity and host naming disclosures while preserving the intended public content; the measure addresses a different trust boundary from the exposed robots instructions finding.

Question 158

Operations asks for a practical correction after the test found: A malicious Android app draws deceptive sign-in prompts above other applications and uses accessibility access to capture typed authentication details. What should the security team recommend?

  1. Use device attestation and restrict access from unsupported rooted endpoints
  2. Enforce managed app sources and mobile threat defense
  3. Enforce HTTPS and prohibit cleartext network policies in app configuration
  4. Restrict risky overlay and accessibility grants and monitor suspicious apps

Explanation

Correct Answer

D:

Platform safeguards and application controls reduce the ability of one app to draw deceptive credential forms over another. It directly addresses this mechanism: overlay attacks abuse user-interface permissions or accessibility features to impersonate legitimate screens and collect credentials.

Incorrect Answers

A:

Integrity checks and conditional access prevent high-trust applications from assuming ordinary platform protections remain intact on modified devices; the required correction concerns mobile overlay credential theft, so this is not the targeted control.

B:

Trusted distribution, signature checks, and endpoint policy reduce installation of repackaged applications from uncontrolled sites; its security benefit applies principally to sideloaded APK risk, not the defect described; the tested fault instead involves mobile overlay credential theft.

C:

TLS protects API exchanges in transit and platform policy stops accidental fallback to unencrypted endpoints; the exposure here is mobile overlay credential theft, which calls for another protective mechanism.

Question 159

The owner asks for a durable safeguard against the issue demonstrated here: Startup measurement reports no longer match known trusted images, and suspicious instructions execute before the operating system's normal kernel services initialize. What is the best response?

  1. Pin and verify dependencies with provenance checks and build isolation
  2. Combine static indicators with isolated dynamic observation
  3. Enable Secure Boot and verify boot integrity measurements
  4. Allowlist trusted software and verify publisher provenance

Explanation

Correct Answer

C:

Signature-based boot validation and attestation make unauthorized boot-chain modifications more difficult to execute unnoticed. The underlying condition is that bootkits target boot components or the boot chain to persist below ordinary user-space defenses, potentially running before endpoint agents initialize.

Incorrect Answers

A:

Signed artifacts, dependency review, and reproducible controls reduce hidden code substitution in otherwise legitimate release pipelines; the tested weakness is bootkit compromise, not the compromised software dependency configuration addressed here.

B:

A controlled sandbox can expose unpacked behavior and runtime imports while avoiding conclusions based only on unusual file entropy; that safeguard does not directly close the bootkit compromise route highlighted by the test.

D:

Approved distribution channels and signed-package review reduce installation of malicious programs masquerading as useful utilities; the specific root cause belongs to bootkit compromise, beyond this control's intended scope.

Question 160

A control review considers a verified technical issue: An endpoint repeatedly executes a malicious technique that changes its packed byte sequence each run, defeating detectors that depend on a single fixed known signature. Which mitigation most directly addresses its cause?

  1. Deploy protected endpoint telemetry on critical hosts
  2. Use approved endpoint telemetry or controlled TLS inspection when justified
  3. Allow outbound destinations and ports based on documented application needs
  4. Combine maintained signatures with behavior and anomaly analytics

Explanation

Correct Answer

D:

Multiple detection approaches address known sequences and unfamiliar variants rather than assuming one byte pattern covers every mutation. It directly addresses this mechanism: signature detection matches established indicators and patterns; changed encodings or previously unseen payloads may evade exact content matches.

Incorrect Answers

A:

Local observation reveals execution and integrity changes not visible from perimeter traffic alone, especially when sessions are encrypted; it would improve host-based intrusion detection, not directly correct the reported signature-based detection issue.

B:

Instrumenting the endpoint or authorized termination point recovers necessary context without assuming a passive sensor can decrypt arbitrary TLS; the measure addresses a different trust boundary from the signature-based detection finding.

C:

Least-privilege egress policy blocks unnecessary command-and-control routes while preserving approved business traffic; the required correction concerns signature-based detection, so this is not the targeted control.

Certified Ethical Hacker v13 (312-50v13) Practice Tests